How are points on the different Dicom views(axial, sagital, and coronal) synced?

I’m trying to label a landmark on one of the views and then be able to sync that mark with the other views and a 3d model reconstruction. From what I understand the image position is the mm position of the slice within the ct scan coordinate system? But how do you correspond bottom point of the heart within the different views? And since the dimensions of the different views are different how is that corresponded to a 3d model reconstruction?